Have used 3.0-r1 without problems for some time and haven't seen any obvious breakage when upgrading to 3.1 now. Reproducible: Always
biblatex-3.2 works also fine.
author  Amy Winston <amynka@gentoo.org> 2016-05-24 15:18:10 (GMT) committer Amy Winston <amynka@gentoo.org> 2016-05-24 15:18:10 (GMT) commit f4d467259984af7358c6a900ce8b3fd0ed4e51cd dev-tex/biblatex: add ~arm keyword bug #564550